Farmers who get a positive BVD test result are now required to remove that calf immediately, vaccinate all female animals and get a whole herd blood test carried out by the farm vet. For the farmer, this is a huge inconvenience at a very busy time of the year.

The cost of all this is covered by the Department.

However, the herd is effectively locked up for a period until blood test results are back, females are vaccinated and investigation is complete.

Herds that are affected can sell stock to non-breeding herds under permit but this restricts where they can be sold

Blood testing can only happen 21 days after positive calf removal and results can take over two weeks to come back so farmers have to plan for approximately five weeks of little or no stock movement on to or off the holding.

Herds that are affected can sell stock to non-breeding herds under permit but this restricts where they can be sold.

Tough stance

The Department of Agriculture and Animal Health Ireland (AHI) are making these changes in the final push to allow Ireland apply to the EU for negative herd status for BVD – 99.8% of herds must be BVD-free for this. Currently, Ireland has over 95% of breeding herds technically BVD-free. If Ireland can attain this “BVD-free” status, compulsory tissue tag testing would not be required after 2022.

Farmer surprise

We had a number of calls from farmers over the last two weeks outlining their surprise at the automatic herd lockup once a BVD positive calf is identified from tissue tag testing.

Most were still comfortable with the overall direction and objective to attain BVD-free status for the country

This new rule came into play on 1 January 2021 and what seemed to frustrate farmers who called us was that their farm contacts, the vet, the Department, the milk processor representatives, etc, didn’t know anything about the new lockup rules.

Most were still comfortable with the overall direction and objective to attain BVD-free status for the country.

What is the key objective of these tough new laws?

To rapidly identify and resolve the small number of herds with positive or inconclusive results for 2021 and 2022 and to minimise the risk of onward spread of infection.

How many herds tested BVD PI in 2020 and do we have any idea of when these positive animals were removed?

Of the 725 animals disclosed as positive in 2020, 616 (85%) were disposed of within 21 days of the initial positive test. Median interval from testing positive to disposal was six days.

It is also encouraging to note that all 2020-born positives have been removed from farms. The median time to removal of positive calves this year is only two days.

How many herds do you expect will have at least one positive test result this year?

Based on previous experience and our best modelling estimates, we expect approximately 250 herds will be affected this year (half dairy and half suckler herds).

A number of the herds already affected have stated they haven’t had a positive BVD case for the last four years. How can you explain this?

The fact is that a cow or heifer which just gave birth to a BVD-positive calf came in contact with a BVD virus when it was going in calf last summer.

Whether that was across a ditch to neighbouring animals or indirectly through movement of people or equipment, that is for the farm to identify and investigate.

How is the cost of vaccinating and blood testing paid for?

The Department is funding this as it is critical to move forward on a national basis towards eradication with payments being made directly to vets by AHI on behalf of the Department.

Why can’t I sell calves if the positive calf is removed from herd?

A positive calf could have infected other herd animals, so the 21-day delay and vaccination acts as a circuit-breaker.

While restricted movements out of the herd to slaughter or to non-breeding herds may be granted on a case-by-case basis under permit by the regional veterinary officer, provided that the animals move directly to their destination.

If a farm gets a positive test case, where do you get permission to move stock?

Farmers should contact their regional veterinary officer. Each herd owner and their vet with a positive result gets a call from the BVD help desk, provided by the Department of Agriculture.

Adjoining herdowners are notified.

Are there any restrictions on the herd where calves move into?

In short, no, but all movement is permitted on a case-by-case basis. Movement is permitted based on negligible risk of contact with pregnant animals so only to non-breeding herds (including for export).

What are the most up-to-date numbers for herds that test positive in 2021?

Regarding numbers, there are just 67 herds so far with positive calves this year – with 0.02% of over 500,000 calves with positive results.

Have you any investigation completed in previous herds that had no exposure previously?

We have a study ongoing to explore factors for herds that were positive for the first time in 2019 and expect to have results from that in the near future.

When do you envisage farmers being able to move away from tissue tag testing? A date of the end of 2022 was mentioned before to move to BVD-free status in 2023 – is this still the target?

That is correct, so the goal remains to cease tissue tag testing nationally by the end of 2022.

If the target end date for tissue tag testing is the end of 2022, will farmers who identify a positive animal between now and then be required to continue tissue tag testing for longer?

Yes, these herds will continue to tissue-test and vaccinate for two years after a positive case has been identified.

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